I had knee problems myself after injuring my ligaments while playing sports. I eventually consulted Dr Alan Cheung, an orthopaedic doctor here in Singapore, and underwent surgery followed by physiotherapy. He explained my treatment options and guided me through the recovery process, which I appreciated. Your mum's knee pain could be due to something different, though, so I'd suggest getting it checked first to find out what's causing the pain. Hope you find the right doctor for her! ❤️